Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

No annotations provided, so description carries full burden. Discloses billing behavior, country-specific IP, residential vs datacenter, and JS rendering. Lacks specifics like timeout, rate limits, or exact response format, but covers major behaviors.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Is the description appropriately sized, front-loaded, and free of redundancy?

Packed with information in a single paragraph. Front-loaded with main function. Could be broken into multiple sentences for easier parsing, but no waste.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

No output schema, but explains return of HTML/JSON and payment_required on insufficient balance. Covers core functionality, billing, and edge cases. Missing timeout or rate limits, but acceptable given tool complexity.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 0%, but description adds meaning to all parameters: url (any), render (JS rendering), country (IP location), agent_id (billing), residential (bypass datacenter blocks). Provides context well beyond bare schema.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Does the description clearly state what the tool does and how it differs from similar tools?

Description clearly states it fetches content from any URL via chosen country IP, handles HTML/JSON, and positions itself as flagship tool. Differentiates from siblings like fetch_ru and get_ru_proxy by covering all URLs and countries.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Does the description explain when to use this tool, when not to, or what alternatives exist?

Explicitly tells when to use: URL in, content out, no proxy setup. Provides guidance on country='ru' for Russia-only sites, residential=true for datacenter-blocking, render=true for JS-heavy sites. Also explains billing and what to do on insufficient balance.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.